Kilojoules to gigawatt hours converter above calculates how many gigawatt hours are in 'X' kilojoules (where 'X' is the number of kilojoules to convert to gigawatt hours). In order to convert a value from kilojoules to gigawatt hours (from kJ to GWh) type the number of kJ to be converted to GWh and then click on the 'convert' button.